We generally do not recommend exercise for the first week post hair transplant, because of the concern that anything that raises your heart rate may increase bleeding. After about 72 hours, light exercise (including walking) will likely be fine. Others may recommend a more liberal or conservative postoperative routine. The actual risk of early exercise to graft take is not well known.
I tell my patients that they can run a marathon within 5 days after the transplant. Sweating will not cause a problem by this time because the grafts should be secure